The invention is related to a lot signalling device used to find misplaced lots.
During the course of processing lots in a pilot line or production factory a lot will be misplaced and will not be available for processing. Additionally, if a lot has been misplaced and forgotten, it might not be processed in a timely manner.
Therefore, tags have been proposed in the prior art, which are attached to the lots. On these tags information about the concerned lot is entered, such as lot number and last and next process steps. With a tag on it a lot can thus unambiguously be identified and handling the lot is made easier for the personnel in a factory, since the immediately preceding and following process steps are indicated on the tag.
However, the data on the tag must be entered and updated by hand and only a relatively limited amount of information is accepted on the tag. Further, the tag is placed with the lot so that it does not help very much in case the lot is misplaced and is not to be found. Only when a misplaced lot is eventually found, it can be identified by the prior art tag on it and reentered into the process again.
Thus, there is a need for a device that prevents lots from getting lost in a production factory between separate process steps.